II.

How Baseball Is Played

A baseball game is divided into nine periods of play, called innings. The team that scores the most runs by the end of the ninth inning wins the game. Play starts when a player called the pitcher throws a ball toward the batter, a player on the opposing team. The batter tries to hit the ball into the baseball field. Players score runs by hitting the ball and running around a series of bases before a player in the field can put them out. Batters and runners can be put out in a variety of ways.

Innings are divided into two halves, referred to as the top and bottom of the inning. During the top of an inning, one team is at bat while the other is in the field. After the team at bat has three outs the two teams switch these roles, and the bottom of an inning begins. If the game is tied after nine innings, the teams continue to play until one has scored more runs at the end of an extra inning.

The following sections describe the elements of baseball in more detail. A knowledge of the design of the field, the use of baseball equipment, and the role of players is crucial to an understanding of how the game is played.

A.

The Field

Baseball is played on a level field, which usually covers about 2 acres (0.8 hectares). (The field dimensions in this section refer to high school, college, and professional baseball. Youth baseball competition, such as Little League, uses smaller dimensions.) The playing area is divided into the infield and the outfield. Together, these two areas make up fair territory. The rest of the field is called foul territory.

The infield consists of a square-shaped plot called the diamond, which measures 90 ft (27 m) on each side. One corner of the diamond is marked by a five-sided piece of rubber called home plate. Batters hit the ball from a position on either side of home plate, depending on their preference. At the three other corners of the infield—moving counterclockwise from home plate—are first base, second base, and third base. Each base is marked with a canvas bag.

The pitcher’s mound, a slightly raised piece of ground, lies near the center of the infield, between home plate and second base. A strip of rubber is nailed to the top of the mound, 60 ft 6 in (about 18 m) from home plate. Pitchers place one foot on the rubber when they put the ball in play.

Base lines run from home plate to first base and from home plate to third base. Extensions of these lines, called foul lines, run along the outer edges of the outfield. These lines divide foul and fair territory. Base lines also extend from first to second to third base, marking the path of a runner. The region of the outfield behind first base is called right field, the region behind second base is called center field, and the region behind third base is called left field. A curving fence runs along the farthest limits of the outfield, typically about 90 to 120 m (300 to 400 ft) away from home plate at various points.

Two covered shelters called dugouts are located in foul territory along each base line. Players occupy the dugouts when they are not on the field. The baseball field is also designed with a number of markings that indicate the use of certain regions. Boxes outlined in chalk on each side of home plate indicate where a batter may stand. Chalk boxes in foul territory near first and third base define the position of team coaches. Similar regions limit where pitchers may warm up during the game and where players may prepare before batting.

B.

Baseball Equipment

Basic baseball equipment includes a hard ball, a wooden or aluminum bat, a padded leather glove for each fielder for catching the ball, cleated shoes, and protective helmets for batters. Catchers wear special protective gear, including a helmet, a cagelike mask, a padded chest protector, and shin guards.

A baseball has a cork center wrapped in layers of rubber and string. It is covered by pieces of leather that have been tightly stitched together. A baseball measures about 9 in (23 cm) in circumference. Bats are usually made of aluminum or of springy wood, such as ash. They may be no more than 2.75 in (7 cm) in diameter and no more than 42 in (107 cm) in length. Specific rules also describe the size and construction of gloves, spiked shoes, batting helmets, and other baseball equipment.

C.

The Baseball Team

A baseball team fields nine players. On the field, each player is responsible for a particular position. The pitcher puts the ball into play by throwing it toward home plate. Each throw is called a pitch. By holding the ball in special ways and adjusting its spin, pitchers can throw a variety of pitches. They use these techniques, along with changing the speed of their throw, to make it more difficult for batters to hit the ball. The catcher receives the ball and returns it to the pitcher unless the batter hits the ball. Catchers also defend home plate when a runner tries to score.

The first baseman, second baseman, and third baseman are each stationed at or near a base. The shortstop stands between second and third base. These players are responsible for fielding, or handling, the ball when it is hit to the infield and for putting out runners as they attempt to advance around the diamond. Three outfielders are stationed individually in right field, center field, and left field. They are responsible for fielding balls hit to the outfield.

While one team is in the field, the other team takes its turn at bat, one player at a time, according to a specific order. Batting rules vary slightly in the two major leagues of the United States. In the National League, the pitcher is also a batter. In the American League, a player called the designated hitter bats in place of the pitcher. Designated hitters do not play on the field.

D.

Managers and Umpires

In organized baseball, several people help the game run smoothly. They include managers, coaches, and umpires.

The manager is a team’s leader and is responsible for the team’s strategy and conduct. Managers determine which members of the team play, what positions they play, and the order in which they bat. During the game, most managers prefer to perform their duties from the dugout, except for occasional visits to the field to remove a pitcher or argue a call with an umpire. Two or more coaches, positioned closer to the field, assist the manager by communicating with the players. For example, managers may decide what pitches should be thrown, when batters should swing at a pitch, and how runners should move around the bases. The manager relays these decisions through special hand signals that the coaches repeat to communicate to the players.

Umpires are responsible for interpreting and enforcing the rules of play. They rule on the results of each play—for example, an umpire determines when a player is out. Umpires have complete authority over the game. They may eject from the game players, managers, or coaches who break rules of conduct. In the major leagues, a crew of four umpires is assigned to each game. They are stationed at home plate, along the first and third base lines, and in the infield near second base.

E.

Basic Rules

In a baseball game, one team is designated the home team and the other is the visiting team. The visiting team always bats first, or at the top of the inning, while the home team takes the field. When a team is at bat it is playing offense—that is, trying to score runs. Teams score runs after their players get on base, primarily by hitting the ball, and then continue around the bases in consecutive order and successfully cross home plate before the third out is made. When a team is in the field it is playing defense, or trying to put opposing players out before they can travel around the bases. After three outs, half of the inning is over and the teams switch sides.

F.

Pitching

Throughout the game, play revolves around the action between the pitcher and the batter. The pitcher has the first opportunity to put the batter out. Pitchers throw the ball to the batter, usually attempting to pass it through the strike zone, an area directly over home plate and roughly between the batter’s armpits and knees. Pitches thrown into this area that the batter does not hit are called strikes. Strikes also include (1) pitches that the batter swings at but does not hit and (2) the first two times that a batter hits the ball into foul territory. (Subsequent fouls do not count as strikes or balls.) After three strikes, a batter is out. Pitches outside of the strike zone that the batter does not swing at are called balls. If a pitcher throws four balls, the batter proceeds to first base. This is called a base on balls or a walk. An umpire determines whether pitches are strikes or balls.

G.

Getting on Base and Running

If a batter gets on base by hitting the ball so that fielders cannot successfully field it, the batter has recorded a base hit. On a base hit, the runner tries to advance as many bases as possible without being put out. A base hit in which a batter gets to first base is called a single; one in which the batter gets to second base is called a double; and one in which the batter gets to third base is called a triple.

Batters can reach first base in several ways, in addition to base hits and walks. The most common are (1) when the batter is hit by a pitched ball; (2) when a fielder mishandles a ball hit in fair territory and the batter reaches base safely as a result of the fielding mistake, known as an error; (3) when the catcher interferes with the batter’s attempt to swing at the pitch; and (4) when the catcher drops a third strike and the batter reaches first base before a fielder tags the base or the batter.

Batters who reach base safely are referred to as base runners. Base runners can proceed to the next base when a subsequent batter hits the ball. If a batted ball is caught on a fly, the runner may advance, but may only leave the current base after the catch is made. Subsequent batters sometimes sacrifice their chance for getting a base hit in order to advance the runner. One way to do this is to hit a sacrifice fly ball. Another way is to bunt—that is, simply hold the bat out toward a pitch rather than swing the bat, so that when the ball is hit, it rolls slowly toward the infield. Ordinarily, in a sacrifice, the batter is put out, and the runner reaches the next base safely.

Runners also may advance by stealing a base. They may steal only under certain circumstances, such as when the pitcher is delivering a pitch or when the catcher drops the ball. To prevent steals, fielders must tag the runners by touching them with the ball.

H.

Fielding

If the batter hits the ball, fielders have opportunities to prevent the batter from reaching a base safely, known as putting the batter out. For example, a batter is ruled out if a fielder catches a batted ball before it hits the ground, in foul or fair territory. A batter is also out if a fielder holding the ball tags the batter or tags first base before the batter can reach it. Fielders often retrieve the ball from where it is hit and throw it to the player covering first base, who tags the base. If the batter reaches first base safely, however, fielders have additional opportunities to put players out and prevent a run. If a runner occupies a base to which a subsequent batter or runner must advance, runners are forced to move to the next base. In a force, fielders can put the runner out by tagging the base before the runner reaches it. If there is no force—that is, if there is no runner approaching from the preceding base—fielders must tag the runner out.

If fielders put two runners out in one play, it is called a double play. If they put three runners out in one play, it is called a triple play. A typical double play occurs when the batter hits the ball on the ground in the infield. As the runner tries to advance from first base to second base, an infielder gets the ball, steps on second base to force out the base runner, and quickly throws the ball to the player covering first base to put out the batter. A triple play is relatively rare in baseball.

I.

Scoring

A runner scores by successfully moving around all the bases and crossing home plate without being put out. Scoring is usually the result of a combination of base hits, walks, or sacrifices; skillful baserunning; or errors by the defensive team. Sometimes the batter circles the bases on one hit. This is known as a home run. A batter usually scores a home run by hitting the ball over the outfield fence. On rare occasions, however, the batter may round all four bases without hitting the ball over the fence. This play is known as an inside-the-park home run. If there are base runners at the time the home run is hit, those players also round the bases and score. If there are base runners on all three bases when the batter hits a home run, the team at bat scores four runs, and the play is called a grand slam.